The invention relates to digital typography.
In digital text composition, a spacing amount between adjacent characters must be set in order to arrange a series of characters in a line of text. In digital text composition, a large number of characters and types of characters are processed, and the spacing amount is typically set based on character attributes. In practice, however, each publishing company has its own rules, and setting the spacing amount between characters in existing electronic composition systems is complicated, leading to operations that are extremely difficult and hard to understand for a user.
Generally, when a computer program, e.g., desktop publishing (DTP) system, is laying out text, the space between a pair of characters is specified by the width of the characters specified in the font, which is typically adjusted by any kerning specified in the font and by any tracking that is applied. Tracking is the process of uniformly increasing or decreasing the space between all glyphs in a block of text and is sometimes called character spacing or letter spacing. Tracking is generally set manually by a user. Thus, when a conventional computer program needs to justify text on both margins, the user can specify the amount of space to add or subtract from between letters (letter spacing) and the amount of space to add or subtract between words (word spacing), but that is all.